Explosively activated bolt-holding wrench



April 21, 19 4 R. A. HARRISON EXPLOSIVELY ACTIVATED BOLT-HOLDING WRENCH 2 Sheets-Sheet 1 Filed Feb. 3, 1961 ROBERT A. HARRISON April 21, 1964- R. A. HARRISON 3,129,619

EXPLOSIVELY ACTIVATED BOLT-HOLDING WRENCH Filed Feb. 3, 1961 2 Sheets-Shed 2 w 38 FIG.5

INVENTOR ROBERT A. HARRISON ATTORNEY United States Patent 3,129,619 EXFLQSIVELY ACTIVATED BELT-HOLDING WRENCH Robert A. Harrison, Washington, D.C. (955 S. Columbus St., Arlington 4, Va.) Filed Feb. 3, 1961, Ser. No. 86,993 10 Claims. (til. 81-525) This invention relates to tools for producing relative rotary motion between two elements and more particularly to a device adapted for loosening or tightening threaded fastenings.

An object of the invention is to provide a device wherein an explosive charge may be controlled so as to produce relative rotary motion between the two elements of a threaded fastener.

Another object is to provide a device of this type wherein a movable vane within a closed chamber may be rotated by an explosive charge so as to exert force to loosen or tighten fasteners.

Another object of the invention is to provide a device of this type for loosening or tightening threaded fastenings wherein a piston which is moved longitudinally of a cylinder by an explosive charge is provided with means to translate the longitudinal movement of the piston into rotary motion to exert effective relative rotational force between the fastener elements.

Still another object is to provide a tool operable by an explosive charge which is readily attachable to threaded fastenings of varying sizes and shapes.

Still another object of the invention is to provide an explosive charge tool capable of producing rotary motion and having auxiliary means to absorb the force generated by operation of the device.

Other objects and advantages of the invention will become apparent from consideration of the following specification with reference to the attached drawings, in which:

FIG. 1 is a side elevation of one form of the device in accordance with this invention;

FIG. 2 is a perspective view of the exterior of the operating mechanism of the apparatus shown in FIG. 1;

FIG. 3 is an adapter member for use with the device shown in FIG. 2;

FIG. 4 is a cross-section taken on the line 4-4 of FIG. 1;

FIG. 5 is a cross-section taken on the line 55 of FIG. 4;

FIG. 6 is a perspective view on an enlarged scale of a portion of the securing means shown in FIG. 1;

FIG. 7 is a longitudinal cross-section of another form of apparatus in accordance with this invention;

FIG. 8 is a cross-section on an enlarged scale taken on the line 88 of FIG. 7;

FIG. 9 is a cross-section on the same scale as FIG. 8 but taken on the line 99 of FIG. 7, and;

FIG. 10 is an end elevation of a modified form of adapter.

Turning now to the drawings, there is shown a cup shaped casing provided with a cover 16 which together form a closed cylindrical chamber within which there is positioned a vane-type piston 17 fixed to one end of a shaft 18 which projects outwardly from the casing through a concentrically located opening in the bottom wall 19 of the casing. This bottom wall and the top wall 20 of the cover are arranged in parallel so that their inner surfaces together with the periphery of the casing form a substantially gas-tight connection with the movable vane. The interior of the casing 15 is also provided with an abutment 21 extending radially from the center of the casing to the inner periphery. When the cover 16 is in place, its inner surface lies flush with the surface of the abutment 21 so that the abutment together with vane 17 divides the interior of the casing into two expansible chambers.

A pair of openings 22 and 23 are provided in the cover adapted to receive a small explosive charge of a type well known in the art as used with other types of tools. These openings are placed near the opposite faces of the abutment 21 so as to be capable of actuation by firing pins 24 and 25 respectively which are received in suitable recesses 26 and 27 in the abutment. The cover 16 is also provided with a pair of J-shaped openings 28 and 29 and the rear ends of the firing pins 36 and 31 respectively are bent laterally to project outwardly through these openings. The firing pins are urged into contact with their respective explosive charges by springs 32 and 33 received behind them in the recesses 26 and 27. Before the explosive charge is inserted in the chamber, the respective firing pins may be cocked from the exterior of the chamber by pulling the rear end 35 or 31 of the respective firing pin back into the short leg of the J shaped opening 23 or 29. As shown in FIG. 2, both firing pins are in the cocked position. To fire the explosive charge, it is only necessary to move the rear end of the firing pin around the bottom of the J-shaped slot and release it at the bottom of the longer leg of the slot. Rotary movement of the piston 17 is limited by means of stops 34 and 35 and a pair of exhaust openings 36 and 37 are arranged in the top wall 20 of the cover at positions such that they Will be uncovered at the end of travel of the piston in either direction. A threaded plug 38 is used to close one or the other of the exhaust openings as will be explained later.

The outer end of shaft 18 is provided with a socket member 39 which is adapted to receive a plurality of adapters, one of which is indicated by numeral 40 in FIG. 3. Each such adapter is provided with a central recess or protuberance 41 which is shaped to receive the particular style of threaded element with which the (adapter is to be used. The adapter is received within the bore 42 of the socket 39 and is provided with one or more radially projecting bosses 43 engageable with the slots 44 to prevent relative rotation.

The cover member 16 is also provided with an outwardly projecting handle 45. A reaction member 46 is provided for the purpose of holding one of the members of a threaded fastening. One end of the reaction member may be secured to the apparatus as by means of a bolt 47 passing through a suitable opening in the handle 45 and secured thereto by means of a nut 48. The reaction member is preferably U-shaped in construction and at its forward end 49 is bifurcated to receive a laterally sliding adapter bar '50 provided with a series of spaced apertures 51 so that the bar may be positioned within the bifurcated portion of the reaction member by means of a pin or bolt 5-2. Several interchangeable adapter bars may be provided, having at one end 50 an upstanding portion 53 which is slotted as at 54 to engage with the particular style of male or female threaded element with which the bar is to be used.

In addition to the reactor member, it is also advantageous to provide a stabilizing support such as the elongated bar 55. A diametrically extending opening 56 is provided in the handle 45 through which the bar can pass to extend outwardly a distance sufficient so that it can be placed in contact with some firm support such as the ground (indicated at 57) and then be positioned by means of pins 58 inserted in the spaced openings "59. An angularly disposed opening 60 is also provided in case it is necessary to extend the stabilizing bar 55 in an angular direction to engage with a firm support.

In operation of the device, it should be noted that in accordance 'with which of the two explosion chambers is used, the shaft 18 can be caused to rotate in either a clockwise or counterclockwise direction. For example, if clockwise rotation is desired, as viewed in FIG. 4, the piston 17 will he initially placed against the stop 34 and the threaded plug 38 will be used to cover the exhaust opening 36. An explosive charge will be inserted in opening 22; the firing pin 24 having first been placed in its cocked position by moving the rear end of the pin 30 into the short leg of the J-shaped opening 23. With the parts arranged thusly, the device is in condition to loosen a lefthand threaded fastening.

In FIG. 1, a bolt 61 is shown holding together two plates 62 and 63 which it is desired to separate. The particular adapter 40 having a recess 41 which fits the head of the bolt 61 is inserted in the socket 39 and the device is put in position as shown. Although it will not always be necessary, it may be of assistance to arrange the stabilizer bar 55 so as to brace the device against a firm support such as the ground 57. With the device in position, an adapter bar 50 having a slot 54 which will fit the nut 64 is attached to the end of the reaction member 46 by means of the pin 52.

When the end 30 of the firing pin is moved over to the longer leg of the J-shaped slot 28, it is released and the spring 32 causes the firing pin 24 to set off the explo sive charge causing the piston 17 to swing around to its dotted line position as shown in FIG. 4, at which point it will uncover the exhaust opening 37 allowing an excess of pressure in the chamber to be relieved. The rotation of the piston turns the shaft 18 together with the socket 39, adapter 40 and bolt 61 while the reaction member as with its adapter bar 50 will prevent the nut 64- from turning. This initial loosening of the bolt will usually make it possible to unthread the nut the rest of the way with an ordinary wrench.

If, on the other hand, it is desired to exert a tightening force on a left-hand fastener after the nut has been fitted on as far as it may be done by hand, the piston 17 would be initially positioned at the desired number of degrees away from the stop 34, the plug 38 would be used to cover the exhaust opening 37 and the exhaust opening 36 would be left clear. Instead of placing the explosive charge in the opening 22, it would be placed in the opening 23 so as to be actuated by the firing pin 25. 'This pin can be cocked, as previously explained, by moving its rear end into the short section of the J-slot 29 and the pin may then be released by moving the end 31 over to the longer leg of the J-slot.

Another form of the invention is shown in FIGS. 7, 8 and 9. In this form, an elongated casing 65 is shown, one end 66 of which forms the handle portion while the other end is provided with a cylindrical bore 67 to receive a longitudinally movable cylindrical piston 68. At the inner end of the bore 67 an opening =69 is provided in the side of the casing to receive an explosive charge similar to those used in the first modification. A firing pin and spring mechanism 70 is also provided adjacent this opening which is operable in the same manner as m the first modification.

A hollow coupling member 71 is supported at one end by means of a spider 72 which positions the coupling concentrically with the bore 67. The other end of the coupling is fixed concentrically to the closed end of an elongated cup-shaped socket member 73. This ar' rangement permits the socket member to rotate with respect to the casing 65, but restrains it against any axial movement with respect thereto. A driving rod 74, attached to the front end of piston 68, extends through the center of the coupling 71 and terminates within the socket with a crossbar 75, the two ends of which are slidably received in a pair of aligned slots '76 and 77 extending in straight lines along opposite sides of the socket. The open end of the socket is adapted to receive any one of the adapters 4i} and is provided 'with inwardly directed slots 78 for engagement with the bosses 43.

The interior of the bore 67 is provided with two pairs of longitudinally extending helical grooves 83 and 81. Only one of each pair of these grooves can be seen in FIG. 7 since the complementary grooves are arranged diametrically opposite within the bore. A pair of guide pins 79 project outwardly from opposite sides of the piston 68 and ride in the grooves when the piston moves longitudinally in the bore. It will be observed that when the pins are in engagement with one pair of grooves, as for example the pair represented by the groove 80, the piston will be given a counterclockwise rotation (as viewed from the right in FIG. 7) when the piston moves from right to left. Similarly, when the pins ride in groove 81, the piston will be given a clockwise movement. Where the grooves approach each other at the inner end of the bore, they are joined by a short circumferentially arranged groove 82, the purpose of which is to permit the piston to be selectively arranged, prior to firing the explosive charge, to turn in either direction when the charge is fired. In order to stabilize the handle 66 against excessive torque, it may be provided with a transverse opening 83 and an angular opening 84 to receive the stabilizing bar 55. A transverse opening 85 is also provided to receive the bolt 47 of the reaction member 46. An exhaust opening 86 is provided in the wall of the casing at a position such that it will become uncovered when the piston 58 has completed its travel to the left as shown in the dotted line position.

In the operation of this modified form of the device, a suitable adapter dt) will be inserted in the open end of the socket 73; The reaction member 46 with the appropriate adapter bar 5i might be placed in position and a stabilizing bar 55 may be attached if desired. The firing pin mechanism 70 is cooked in a manner similar to that described in connection with the first form of the device and an explosive charge is inserted in the opening 69. The direction of rotation may be chosen by rotation of the socket 73 to bring the pins 79 into alignment with either of the grooves 80 or 81. Counterclockwise rotation of the socket (as viewed from the right in FIG. 7) will bring the pins into alignment with grooves 80. Thereafter, when the firing pin is released and the charge explodes, the piston will be driven forward (to the left as shown in FIG. 7) and the pins riding in grooves 80 will cause the rod 74 and crossbar 75 to move forwardly and at the same time, rotate in a counterclockwise direction. Since the socket is restrained against longitudinal movement by the coupling 71, there will be no forward movement of the socket but it will rotate in a counterclockwise direction as the crossbar moves forward in the longitudinally extending slots 76 and 77. At the end of its forward travel, the crossbar will have turned through an angle of degrees as indicated by the dotted lines. However, it will be understood that the pitch of grooves 89 and 81 may be varied to provide any amount of rotation of the socket.

Similarly, it will be understood that if the socket is rotated in a clockwise direction to position the pins 79 in alignment with grooves 81, prior to firing the explosive charge, the socket will be given clockwise rotation when the explosive charge is fired.

A modified form of adapter which can be used with objects of circular or irregular configuration is shown in FIG. 10. This form of adapter is provided with a cylindrical body portion 87 having radially extending bosses 38. The interior of the body is cut out to provide a square cavity 89 and a pair of oppositely disposed jaws 99 are slidably positioned therein. Preferably, the faces of these jaws 91 are serrated so as to grip irregularly shaped objects. The jaws may be urged inwardly toward each other as by means of the threaded members 92 which pass through suitably threaded openings in a pair of oppositely disposed bosses 88.

Having now described the invention in detail, it will be understood that various improvements and modifications may be made in the invention within the scope of the appended claims.

I claim:

1. In a tool for operating threaded fasteners of the character wherein two elements are rotatable with respect to each other, the combination including a closed cylindrical chamber having parallel end walls, a rotatable shaft projecting outwardly from said chamber normal to said walls, a movable vane piston extending between said parallel walls and fixed to said shaft, a radially extending wall forming with said vane piston an expansible chamber, means to removably position an explosive cartridge means in said expansible chamber, means to secure said cylindrical chamber to one element of said fastener, means to secure said shaft to the other fastener element, and means to ignite said explosive charge in said closed chamber to move said vane.

2. The invention as defined in claim 1, wherein the interior of said closed chamber is provided with a radial abutment extending between said parallel walls, and means to selectively ignite an explosive charge in said chamber between said abutment and either side of said movable vane to selectively rotate said vane in opposite directions.

3. The invention as defined in claim 2, wherein said chamber is provided with two exhaust openings for combustion gases, and means to selectively close either one of said openings to permit said selective rotation of the vane.

4. The invention as defined in claim 1, wherein said means to ignite an explosive charge includes a firing pin, and biasing means to urge said pin into engagement with said charge, one of the walls of said closed chamber being provided with a J-shaped slot, said pin having a laterally extending portion projecting exteriorly of the chamber slidingly received in said slotted portion.

5. The invention as defined in claim 1, wherein said shaft includes a member movable with said piston, and adapter means to be detachably connected with said movable member, said adapter means also having means to engage with one of said fastener elements.

6. The invention as defined in claim 5, wherein said adapter means is rotatable about a central axis and is provided with a movable clamping jaw means to engage with fastener elements of varying dimensions and to position the fastener element concentrically with said central axis.

7. The invention as defined in claim 1, wherein said means to secure said chamber to a fastener element includes a reaction member projecting forwardly of said engagement means, said reaction member having adapter means to be detachably secured to said fastener element.

8. The invention as defined in claim 7, wherein said reaction member includes means to position said adapter means axially adjustably with respect to said engagement means.

9. The invention as defined in claim 8, wherein said adapter means includes a bar provided with a laterally extending portion adapted to engage with a fastener element, and means to attach said reaction means to said bar at a plurality of locations along the length thereof.

10. In a tool for exerting rotational force against an element, the combination including expansible chamber motor means having a vane-type piston means rotatable more than about a fixed axis, means to ignite an explosive charge Within said expansible chamber to rotate said piston means, means to detachably connect said piston to said element to be rotated, and means connected with said expansible chamber to resist the reaction force developed when said explosive charge is ignited.

References Cited in the file of this patent UNITED STATES PATENTS 1,072,701 Collins Sept. 9, 1913 1,097,288 Bidinger May 19, 1914 2,107,108 De Mooy Feb. 1, 1938 2,112,693 Douglass Mar. 29, 1938 2,276,259 Temple Mar. 10, 1942 2,502,587 Phipps Apr. 4, 1950 2,600,214 Davis June 10, 1952 61 Meyer et al July 8, 1952 2,633,042 Halverson Mar. 31, 1953 2,672,308 Farrell Mar. 16, 1954 2,974,645 Wik Mar. 14, 1961 2,981,130 Broske et a1. Apr. 25, 1961 

1. IN A TOOL FOR OPERATING THREADED FASTENERS OF THE CHARACTER WHEREIN TWO ELEMENTS ARE ROTATABLE WITH RESPECT TO EACH OTHER, THE COMBINATION INCLUDING A CLOSED CYLINDRICAL CHAMBER HAVING PARALLEL END WALLS, A ROTATABLE SHAFT PROJECTING OUTWARDLY FROM SAID CHAMBER NORMAL TO SAID WALLS, A MOVABLE VANE PISTON EXTENDING BETWEEN SAID PARALLEL WALLS AND FIXED TO SAID SHAFT, A RADIALLY EXTENDING WALL FORMING WITH SAID VANE PISTON AN EXPANSIBLE CHAMBER, MEANS TO REMOVABLY POSITION AN EXPLOSIVE CARTRIDGE MEANS IN SAID EXPANSIBLE CHAMBER, MEANS TO SECURE SAID CYLINDRICAL CHAMBER TO ONE ELEMENT OF SAID FASTENER, MEANS TO SECURE SAID SHAFT TO THE OTHER FASTENER ELEMENT, AND MEANS TO IGNITE SAID EXPLOSIVE CHARGE IN SAID CLOSED CHAMBER TO MOVE SAID VANE. 